本酶催化的反应为Hydrolysis Of (1->4)-alpha-D-Glucosidic Linkages In Polysaccharides So As To Remove Successive Maltose Units From The Non-Reducing Ends Of The Chains,系统名称为4-alpha-D-Glucan Maltohydrolase,作用于淀粉、糖原及相关多糖和寡糖,通过转化产生 β-麦芽糖。“β”一词涉及所释放游离糖基的初始异头构型,而非所水解键的构型。